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Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by Gregozedobe

The "Locator glow" of my PALights is much, much lower that the 0.2 lumens of my ZL SC60, and is only useable once my eyes have had several minutes of dark adaptation. The lowest setting of my white LED photon is a little lower than the PALight, and my NVG Photon running on 1xCR2032 mattery is lower again (I have to ramp it up slightly to use it for navigating around my house at night).

One of my PALights has a much dimmer "Locator glow" than all the rest, and is way too low to use to see anything beyond finding it in the dark.

I ordered three PALights last week, a red a green and a white. I'll let you know if the located glow on them is around .04 lumens or not. My guess is they must be if the locator glow lasts a year

I'm glad I found CPF, I was beginning to think I was strange
I'm a Canadian and a proud Flashaholic
Thanks CPF, thanks Think2x

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by Gregozedobe

..The lowest setting of my white LED photon is a little lower than the PALight, and my NVG Photon running on 1xCR2032 battery is lower again (I have to ramp it up slightly to use it for navigating around my house at night)...

A Covert nose NVG PF on 1xCR2032 is the ultimate in control for experiments in dark adapted vision, IMHO.

It just now occurs to me that a Covert nose Photon Freedom in a deep red would be a very powerful experimenter's tool. The PF's UI would be the ultimate in control for deep red, too, having multiple output levels on the low end most certainly below human perception. The PFs and de-powered PFs are some of the few lights with dim enough output to be able to do serious experiments.

The biggest obstacle to meaningful experiments in dark adapted vision, IMO, is often the difficulty involved in finding lights that can go dim enough in the color(s) you want to play with.

Re: Looking for light with deep red led(s) (640nm-690nm)

According to this extremely comprehensive thread it seems the Sunwayman V10 is best suited for very fine dimming in the absolute low regions - exactly what i am looking for in my light. Now, unless someone has a better idea, with a light like this one could think about an emitter swap.

Re: Looking for light with deep red led(s) (640nm-690nm)

I don't own a Sunwayman, so CarpentryHero might be able to help you here, but it appears that the reflector assmebly and body tube on these lights is separate; if that's the case, you could remove that part and have a bare emitter/full flood light. I have an older Jetbeam that does this, and it's an extremely useful feature.

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by MikeAusC

Why not buy some budget Neutral Density Filters for cameras. An ND8 is readily available and reduces light levels by a factor of 8 across the whole visible spectrum.

I have used theatrical filters many times to knock down task lights to an appropriate output level and color, but only as a last resort. It's ok if that is all one can do but I find the filters become another abstraction layer between me and the light. I find the subject of dark adapted vision to be complex, convoluted and very often counterintuitive. For me the filters are too unstable and distracting.

Re: Looking for light with deep red led(s) (640nm-690nm)

I have been following this post with interest. I have a couple of suggestions.

The reddest of my led lights are the low red on my RA Twisty 85Tr (Discontinued) which uses the red side led on it's emitter - an Osram Golden Dragon - a superb light and the low red is ideal for night adapted eyes (I use it when I'm indulging in my astronomy hobby - also when checking on the kids at night). An honourable mention must go to the Quark RGB - it's got a CREE RGB MCE led and is also discontinued!!! The low on this is even lower than the Ra and the high is very bright.

I have emailed First Light USA to see what the wavelength is of their red 5mm leds in my Tomahawk MC and ST, they seem more red and less orange than most - but nowhere near as low as the others on their lowest setting.

BTW I have the Sunwayman V10 Ti and also a Nitecore Infilux IFE2 - both variable output designs - the Nitecore has the lower low (much much lower!) so should be in consideration for Red led modding.

Re: Looking for light with deep red led(s) (640nm-690nm)

BTW I have the Sunwayman V10 Ti and also a Nitecore Infilux IFE2 - both variable output designs - the Nitecore has the lower low (much much lower!) so should be in consideration for Red led modding.

That info comes in very handy indeed! Do both lights have the exact same dimming range in the absolute low regions? I know of the Nightcore's longer overall dynamic range. Would you also agree with that post: Should i therefore be worried about Nitecore's negative aspects of their UI too much?

Re: Looking for light with deep red led(s) (640nm-690nm)

Never handled the Nitecore ife2 but I do own a Sunwayman and it is a very smooth transition in brightness with the magnetic control ring.

On a different note my Palight showed and the red is the lowest low of the three colors whirs in the middle and green is the brightest.

I've been sitting in the dark for a half hour waiting for my sun to fall asleep and the located glow is just that, enough to find the light in the dark. The red may not be as dark as you like but it is nice red to my eyes...
Now you have me curious about the darker red led. PALight is definitely worth what I paid for them the low is what I was looking for, A light to check on my little buddy.

Have u figured out what route you'll take yet?

I'm glad I found CPF, I was beginning to think I was strange
I'm a Canadian and a proud Flashaholic
Thanks CPF, thanks Think2x

Re: Looking for light with deep red led(s) (640nm-690nm)

I don't own a Sunwayman, so CarpentryHero might be able to help you here, but it appears that the reflector assmebly and body tube on these lights is separate; if that's the case, you could remove that part and have a bare emitter/full flood light. I have an older Jetbeam that does this, and it's an extremely useful feature.

Just did that with a light of mine: 90 degrees of pure flood - just perfect! (probably won`t be waterproof anymore)

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by StarHalo

A simple emitter swap on a Sunwayman V series is what comes to mind, since it is infinitely variable and actually dims low enough for night vision purposes; but this would still be several times more expensive than the Rigel..

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by mandat

That info comes in very handy indeed! Do both lights have the exact same dimming range in the absolute low regions? I know of the Nightcore's longer overall dynamic range. Would you also agree with that post: Should i therefore be worried about Nitecore's negative aspects of their UI too much?

Yes generally I agree with the pros and cons in the post you refer to. But I don't find the strobe too annoying to initiate by mistake.

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by afraidofdark

Wow that's rad ... is that for your personal collection, or are you putting it up for sale (hint, hint)

Yes it's my personal light, I have both V10A and V10R that I swapped both to HCRI XP-G. I decided (because this thread got my curiosity going) to swap the V10A to the red XP-E, it is a simple reflow job. Let's just say anything can be for sale.

Originally Posted by mandat

I`ll take it!

Seriously, looks great. Is that 660nm? How difficult was that to do?

Not 660nm, it's an XP-E 625nm but I can tell you it's a real red to me, I see NO orange in it. Digikey only has 625nm and 590nm in the CREE XP-E and I needed/wanted the XP footprint so I could reflow the swap onto the factory board. It matches color very similar to my Inova X5 red, goes very low and blindingly bright on the 123 body.

Re: Looking for light with deep red led(s) (640nm-690nm)

> 630 not 660
Doubt that matters; I'd guess they used the LEDs that were available a few years ago -- those closeouts are a fairly old design from Axiom.

The last time I looked up a manufacturer's offering (Rebels, I think it was), to specify a wavelength exactly required buying a thousand LEDs -- then they'd test until they could sell you ones that matched your spec within a very narrow range. For smaller lots you get something in a broader range, but not tested and sorted, just "in the range" for that LED.

Photosynthesis varies -- "Most plants had photosynthetic action near or over 90% of peak at all wavelengths from 610 to 680 nm, and near or over 80% of peak from 590 to 685 nm." http://donklipstein.com/photosyn.html (fairly old info, links in the original)

Here (Fig. 1 of the pdf) are the absorption curves for a variety of different photosynthesis pigments; this is likely where the manufacturers will be aiming to produce plant growth lights. You can see how broad the curves are. And each species or variety will have a different mix of pigments.http://lib.tkk.fi/Diss/2008/isbn9789...9512295029.pdf

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by anuragwap

This may be a little off topic, but I had to reply to this post since I also love deep red and I'd like to know the options for low/mid power deep red leds.
I have seen many cars whose third brake light is deep red, and also bright. Any ideas what these LEDs are?

I know Osram has some bright super red(633nm) topleds, but probably they'd still be orange-red, and their hyper red(640nm) ones are not bright at all.

Those are the ones I have and would use for my custom flashlight - they are VERY bright:

Re: Looking for light with deep red led(s) (640nm-690nm)

Originally Posted by anuragwap

Thanks for these links, I already have the Ledengin LZ4 deep red, also I've lumex ssl-lx5093src/f (640nm) 5mm leds, I also know of other high power options like oslon ssl80 or rebel deep red, but I was wondering about the leds used in car brake lights. I think I'll give the topleds a try. (Sorry,shouldn't have used the term 'low/mid power', actually I was meaning something in 50-70mA territory)

confusion on my side actually - but the Kingbright led cluster of 50 640nm leds should do the job - those things are quite practical for all sorts of applications - I really like the sparkly appearance of that arrangement - nice to look at, especially when dimmed down to a darker tone - you can`t do that with a high power led